Published on Aug 4, 2016After four years on Mars, Curiosity rover and her operations team are now seasoned explorers, anxious to climb to greater heights on Mount Sharp.

Actually Curiosity is only a machine somewhat the worse for wear. It is the team who are the seasoned explorers

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"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

After collecting drilled rock powder in arguably the most scenic landscape yet visited by a Mars rover, NASA's Curiosity mobile laboratory is driving toward uphill destinations as part of its two-year mission extension that commenced Oct. 1.

The destinations include a ridge capped with material rich in the iron-oxide mineral hematite, about a mile-and-a-half (two-and-a-half kilometers) ahead, and an exposure of clay-rich bedrock beyond that.

These are key exploration sites on lower Mount Sharp, which is a layered, Mount-Rainier-size mound where Curiosity is investigating evidence of ancient, water-rich environments that contrast with the harsh, dry conditions on the surface of Mars today.

"We continue to reach higher and younger layers on Mount Sharp," said Curiosity Project Scientist Ashwin Vasavada, of NASA's Jet Propulsion Laboratory, Pasadena, California. "Even after four years of exploring near and on the mountain, it still has the potential to completely surprise us."

Hundreds of photos Curiosity took in recent weeks amid a cluster of mesas and buttes of diverse shapes are fresh highlights among the more than 180,000 images the rover has taken since landing on Mars in August 2012. Newly available vistas include the rover's latest self-portrait from the color camera at the end of its arm and a scenic panorama from the color camera at the top of the mast.

"Bidding good-bye to 'Murray Buttes,' Curiosity's assignment is the ongoing study of ancient habitability and the potential for life," said Curiosity Program Scientist Michael Meyer at NASA Headquarters, Washington. "This mission, as it explores the succession of rock layers, is reading the 'pages' of Martian history -- changing our understanding of Mars and how the planet has evolved. Curiosity has been and will be a cornerstone in our plans for future missions."

The component images of the self-portrait were taken near the base of one of the Murray Buttes, at the same site where the rover used its drill on Sept. 18 to acquire a sample of rock powder. An attempt to drill at this site four days earlier had halted prematurely due to a short-circuit issue that Curiosity had experienced previously, but the second attempt successfully reached full depth and collected sample material. After departing the buttes area, Curiosity delivered some of the rock sample to its internal laboratory for analysis.

Curiosity's Rock or Soil Sampling Sites on Mars, Through September 2016Curiosity's Rock or Soil Sampling Sites on Mars, Through September 2016This graphic maps locations of the sites where NASA's Curiosity Mars rover collected its first 18 rock or soil samples for laboratory analysis inside the vehicle. It also presents images of the drilled holes where 14 rock-powder samples were acquired, most recently at "Quela," on Sept. 18, 2016.

This latest drill site -- the 14th for Curiosity -- is in a geological layer about 600 feet (180 meters) thick, called the Murray formation. Curiosity has climbed nearly half of this formation's thickness so far and found it consists primarily of mudstone, formed from mud that accumulated at the bottom of ancient lakes. The findings indicate that the lake environment was enduring, not fleeting. For roughly the first half of the new two-year mission extension, the rover team anticipates investigating the upper half of the Murray formation."We will see whether that record of lakes continues further," Vasavada said. "The more vertical thickness we see, the longer the lakes were present, and the longer habitable conditions existed here. Did the ancient environment change over time? Will the type of evidence we've found so far transition to something else?"

The "Hematite Unit" and "Clay Unit" above the Murray formation were identified from Mars orbiter observations before Curiosity's landing. Information about their composition, from the Compact Reconnaissance Imaging Spectrometer aboard NASA's Mars Reconnaissance Orbiter, made them high priorities as destinations for the rover mission. Both hematite and clay typically form in wet environments.

Vasavada said, "The Hematite and the Clay units likely indicate different environments from the conditions recorded in older rock beneath them and different from each other. It will be interesting to see whether either or both were habitable environments."

NASA approved Curiosity's second extended mission this summer on the basis of plans presented by the rover team. Additional extensions for exploring farther up Mount Sharp may be considered in the future. The Curiosity mission has already achieved its main goal of determining whether the landing region ever offered environmental conditions that would have been favorable for microbial life, if Mars has ever hosted life. The mission found evidence of ancient rivers and lakes, with a chemical energy source and all of the chemical ingredients necessary for life as we know it.

The mission is also monitoring the modern environment of Mars, including natural radiation levels. Along with other robotic missions to the Red Planet, it is an important piece of NASA's Journey to Mars, leading toward human crew missions in the 2030s. JPL, a division of Caltech in Pasadena, California, manages the Mars Science Laboratory Project for NASA's Science Mission Directorate and built the project's Curiosity rover. For more information about Curiosity, visit:

Laser-zapping of a globular, golf-ball-size object on Mars by NASA's Curiosity rover confirms that it is an iron-nickel meteorite fallen from the Red Planet's sky.

Iron-nickel meteorites are a common class of space rocks found on Earth, and previous examples have been seen on Mars, but this one, called "Egg Rock," is the first on Mars examined with a laser-firing spectrometer. To do so, the rover team used Curiosity's Chemistry and Camera (ChemCam) instrument.

Scientists of the Mars Science Laboratory (MSL) project, which operates the rover, first noticed the odd-looking rock in images taken by Curiosity's Mast Camera (Mastcam) at a site the rover reached by an Oct. 27 drive.

"The dark, smooth and lustrous aspect of this target, and its sort of spherical shape attracted the attention of some MSL scientists when we received the Mastcam images at the new location," said ChemCam team member Pierre-Yves Meslin, at the Research Institute in Astrophysics and Planetology (IRAP), of France's National Center for Scientific Research (CNRS) and the University of Toulouse, France.

ChemCam found iron, nickel and phosphorus, plus lesser ingredients, in concentrations still being determined through analysis of the spectrum of light produced from dozens of laser pulses at nine spots on the object. The enrichment in both nickel and phosphorus at some of the same points suggests the presence of an iron-nickel-phosphide mineral that is rare except in iron-nickel meteorites, Meslin said.

Iron meteorites typically originate as core material of asteroids that melt, allowing the molten metal fraction of the asteroid's composition to sink to the center and form a core.

"Iron meteorites provide records of many different asteroids that broke up, with fragments of their cores ending up on Earth and on Mars," said ChemCam team member Horton Newsom of the University of New Mexico, Albuquerque. "Mars may have sampled a different population of asteroids than Earth has."

In addition, the study of iron meteorites found on Mars -- including examples found previously by Mars rovers -- can provide information about how long exposure to the Martian environment has affected them, in comparison with how Earth's environment affects iron meteorites. Egg Rock may have fallen to the surface of Mars many millions of years ago. Researchers will be analyzing the ChemCam data from the first few laser shots at each target point and data from subsequent shots at the same point, to compare surface versus interior chemistry.

Egg Rock was found along the rover's path up a layer of lower Mount Sharp called the Murray formation, where sedimentary rocks hold records of ancient lakebed environments on Mars. The main science goal for Curiosity's second extended mission, which began last month, is to investigate how ancient environmental conditions changed over time. The mission has already determined that this region once offered conditons favorable for microbial life, if any life ever existed on Mars.

Curiosity was launched five years ago this month, on Nov. 26, 2011, from Cape Canaveral Air Force Station, Florida. It landed inside Gale Crater, near the foot of Mount Sharp, in August 2012.

The rover remains in good condition for continuing its investigations, after working more than twice as long as its originally planned prime mission of about 23 months, though two of its 10 science instruments have recently shown signs of potentially reduced capability. The neutron-generating component of Curiosity's Dynamic Albedo of Neutrons (DAN) instrument, designed for working through the prime mission, is returning data showing reduced voltage. Even if DAN could no longer generate neutrons, the instrument could continue to check for water molecules in the ground by using its passive mode. The performance of the wind-sensing capability from Curiosity's Rover Environmental Monitoring Station (REMS) is also changing, though that instrument still returns other Mars-weather data daily, such as temperatures, humidity and pressure. Analysis is in progress for fuller diagnosis of unusual data from DAN, which was provided by Russia, and REMS, provided by Spain.

The U.S. Department of Energy's Los Alamos National Laboratory in Los Alamos, New Mexico, developed ChemCam in partnership with scientists and engineers funded by the French national space agency (CNES). Mastcam was built by Malin Space Science Systems, San Diego. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate, Washington, and built the project's Curiosity rover. For more information about Curiosity, visit:

NASA’s Curiosity Mars rover continues to investigate higher and younger strata on the central mountain of Gale Crater, adding information about water-rich ancient environments in this part of Mars. Since reaching the base of the mountain two years ago, the rover has examined more than half the vertical extent of a 180-meter-thick geological formation that provides a record of long-lived lake and groundwater environments. Analysis of rock composition at multiple sites is providing new evidence about how the environmental conditions evolved over time, including factors favorable for life, if it ever was present. Some ingredients may foreshadow what the mission will find at planned destinations farther up the mountain.

Mars Rock-Ingredient Stew Seen as Plus for HabitabilityNow and Long Ago at Gale Crater, MarsThis pair of drawings depicts the same location at Gale Crater on at two points in time: now and billions of years ago. Water moving beneath the ground, as well as water above the surface in ancient rivers and lakes, provided favorable conditions for microbial life, if Mars has ever hosted life. Credit: NASA/JPL-Caltech› Full image and caption | Additional imagesFast Facts:

› NASA's Curiosity Mars rover is finding patterns of change in rock composition at higher, younger layers of a mountain.

› Ancient Mars sedimentary basins with groundwater were chemically active, a factor favorable for possible life.

› Curiosity found boron on Mars, a first for this very soluble element.

NASA's Curiosity rover is climbing a layered Martian mountain and finding evidence of how ancient lakes and wet underground environments changed, billions of years ago, creating more diverse chemical environments that affected their favorability for microbial life.

Hematite, clay minerals and boron are among the ingredients found to be more abundant in layers farther uphill, compared with lower, older layers examined earlier in the mission. Scientists are discussing what these and other variations tell about conditions under which sediments were initially deposited, and about how groundwater moving later through the accumulated layers altered and transported ingredients.

Effects of this groundwater movement are most evident in mineral veins. The veins formed where cracks in the layers were filled with chemicals that had been dissolved in groundwater. The water with its dissolved contents also interacted with the rock matrix surrounding the veins, altering the chemistry both in the rock and in the water.

"There is so much variability in the composition at different elevations, we've hit a jackpot," said John Grotzinger, of Caltech in Pasadena, California. He and other members of Curiosity's science team presented an update about the mission Tuesday, Dec. 13, in San Francisco during the fall meeting of the American Geophysical Union. As the rover examines higher, younger layers, researchers are impressed by the complexity of the lake environments when clay-bearing sediments were being deposited, and also the complexity of the groundwater interactions after the sediments were buried.

'Chemical Reactor'

"A sedimentary basin such as this is a chemical reactor," Grotzinger said. "Elements get rearranged. New minerals form and old ones dissolve. Electrons get redistributed. On Earth, these reactions support life."

Whether Martian life has ever existed is still unknown. No compelling evidence for it has been found. When Curiosity landed in Mars' Gale Crater in 2012, the mission's main goal was to determine whether the area ever offered an environment favorable for microbes.

The crater's main appeal for scientists is geological layering exposed in the lower portion of its central mound, Mount Sharp. These exposures offer access to rocks that hold a record of environmental conditions from many stages of early Martian history, each layer younger than the one beneath it. The mission succeeded in its first year, finding that an ancient Martian lake environment had all the key chemical ingredients needed for life, plus chemical energy available for life. Now, the rover is climbing lower on Mount Sharp to investigate how ancient environmental conditions changed over time.

"We are well into the layers that were the main reason Gale Crater was chosen as the landing site," said Curiosity Deputy Project Scientist Joy Crisp of NASA's Jet Propulsion Laboratory, in Pasadena, California. "We are now using a strategy of drilling samples at regular intervals as the rover climbs Mount Sharp. Earlier we chose drilling targets based on each site's special characteristics. Now that we're driving continuously through the thick basal layer of the mountain, a series of drill holes will build a complete picture."

Four recent drilling sites, from "Oudam" this past June through "Sebina" in October, are each spaced about 80 feet (about 25 meters) apart in elevation. This uphill pattern allows the science team to sample progressively younger layers that reveal Mount Sharp's ancient environmental history.

Changing Environments

One clue to changing ancient conditions is the mineral hematite. It has replaced less-oxidized magnetite as the dominant iron oxide in rocks Curiosity has drilled recently, compared with the site where Curiosity first found lakebed sediments. "Both samples are mudstone deposited at the bottom of a lake, but the hematite may suggest warmer conditions, or more interaction between the atmosphere and the sediments," said Thomas Bristow of NASA Ames Research Center, Moffett Field, California. He helps operate the Chemistry and Mineralogy (CheMin) laboratory instrument inside the rover, which identifies minerals in collected samples.

Chemical reactivity occurs on a gradient of chemical ingredients' strength at donating or receiving electrons. Transfer of electrons due to this gradient can provide energy for life. An increase in hematite relative to magnetite indicates an environmental change in the direction of tugging electrons more strongly, causing a greater degree of oxidation in iron.

Another ingredient increasing in recent measurements by Curiosity is the element boron, which the rover's laser-shooting Chemistry and Camera (ChemCam) instrument has been detecting within mineral veins that are mainly calcium sulfate. "No prior mission has detected boron on Mars," said Patrick Gasda of the U.S. Department of Energy's Los Alamos National Laboratory, Los Alamos, New Mexico. "We're seeing a sharp increase in boron in vein targets inspected in the past several months." The instrument is quite sensitive; even at the increased level, boron makes up only about one-tenth of one percent of the rock composition.

'Dynamic System'

Boron is famously associated with arid sites where much water has evaporated away -- think of the borax that mule teams once hauled from Death Valley. However, environmental implications of the minor amount of boron found by Curiosity are less straightforward than for the increase in hematite.

Scientists are considering at least two possibilities for the source of boron that groundwater left in the veins. Perhaps evaporation of a lake formed a boron-containing deposit in an overlying layer, not yet reached by Curiosity, then water later re-dissolved the boron and carried it down through a fracture network into older layers, where it accumulated along with fracture-filling vein minerals. Or perhaps changes in the chemistry of clay-bearing deposits, such as evidenced by the increased hematite, affected how groundwater picked up and dropped off boron within the local sediments.

"Variations in these minerals and elements indicate a dynamic system," Grotzinger said. "They interact with groundwater as well as surface water. The water influences the chemistry of the clays, but the composition of the water also changes. We are seeing chemical complexity indicating a long, interactive history with the water. The more complicated the chemistry is, the better it is for habitability. The boron, hematite and clay minerals underline the mobility of elements and electrons, and that is good for life."

Curiosity is part of NASA's ongoing Mars research and preparation for a human mission to Mars in the 2030s. Caltech manages JPL, and JPL manages the Curiosity mission for NASA's Science Mission Directorate in Washington. For more about Curiosity, visit:

More specifically, the drill is acting up, and JPL doesn't want to move the arm or drive until the issue is understood. The problem started on December 1.

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Curiosity is at a site on lower Mount Sharp selected for what would be the mission's seventh sample-collection drilling of 2016. The rover team learned Dec. 1 that Curiosity did not complete the commands for drilling. The rover detected a fault in an early step in which the "drill feed" mechanism did not extend the drill to touch the rock target with the bit.

"We are in the process of defining a set of diagnostic tests to carefully assess the drill feed mechanism. We are using our test rover here on Earth to try out these tests before we run them on Mars," Curiosity Deputy Project Manager Steven Lee, at NASA's Jet Propulsion Laboratory in Pasadena, California, said Monday. "To be cautious, until we run the tests on Curiosity, we want to restrict any dynamic changes that could affect the diagnosis. That means not moving the arm and not driving, which could shake it."

Engineers suspect a piece of foreign object debris may be intermittently stalling a motor needed to place the Curiosity Mars rover’s drill bit onto rocks, and the robot’s ground team is assessing the source of the potential contamination.

More importantly, Curiosity project manager Jim Erickson said, engineers are spending the holidays crunching data from a series of diagnostic tests conducted in recent weeks to analyze the drill’s behavior and determine a possible fix.

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Ground controllers believe the drill problem is rooted in a brake on the drill feed mechanism, which is supposed to extend and place the drill bit on the surface of target rocks.

When Curiosity goes in to drill into Martian rocks, the rover extends its robotic arm and two prongs on each side of the drill bit press against the target. The drill feed motor then engages to push the bit onto the rock, then percussive and rotating mechanisms start boring into the target to collect a powder sample.

Erickson told Spaceflight Now that the drill problem, first encountered Dec. 1, has cropped up off and on, but ground controllers have only commanded the motor to move in tiny increments in their testing.

Rover drivers at NASA’s Jet Propulsion Laboratory in Pasadena, California, have also sent Curiosity on short trips and activated shakers inside the drill to test the feed motor’s response to motion, Erickson told Spaceflight Now in JPL’s “Mars yard” facility where engineers test out rover models in simulated Martian terrain.

The shakers are normally used to sort the powder sample acquired by the drill.

Experts believe they found a pattern in the way the drill feed motor behaves over time, Eriskson said, and the pattern observed so far matches what engineers would expect to see if a piece of foreign object debris, or FOD, was embedded somewhere inside the drill.

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He described a “fishbone” diagram used by the investigation team, with arrows splitting off pointing to FOD of terrestrial and Martian origin. Then there’s another split in the fishbone, Erickson said, illustrating two more possibilities, assuming the contamination came from Earth.

“Was it something that the rover carried from Earth from before the launch, or was it generated after the launch?” Erickson asked.

Parts inside the drill may have rubbed together over the last four years since Curiosity’s landing on Mars in August 2012, creating shavings or fragments that are lodged inside the feed motor.

If operating the drill on Mars somehow created the FOD, engineers might be able to change the way they use the instrument, and improve the design of future drills, such as the device in development to fly on NASA’s Mars 2020 rover, a spacecraft largely based on Curiosity’s design and chassis.

Erickson said the rover team is still examining how to resume drilling with Curiosity, and it is too early to declare that engineers can fully correct the problem, or that the issue will prevent future drillings.

It may turn out that the stalled motor remains intermittent, he said, making it a nuisance for ground controllers commanding the rover, but not fatal for the future of the drill.

This is rather curious considering how rare they are on Earth that it keeps coming across metallic meteorites on Mars.

Mars Curiosity Rolls Up to Potential New Meteorite

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Why no large stony meteorites have yet to be been found on Mars is puzzling. They should be far more common; like irons, stonies would also display beautiful thumprinting and dark fusion crust to boot. Maybe they simply blend in too well with all the other rocks littering the Martian landscape. Or perhaps they erode more quickly on Mars than the metal variety.

Every time a meteorite turns up on Mars in images taken by the rovers, I get a kick out of how our planet and the Red One not only share water, ice and wind but also getting whacked by space rocks.

This is rather curious considering how rare they are on Earth that it keeps coming across metallic meteorites on Mars.

Not really surprising. On Earth they rust quite quickly, on Mars they don't. Processes of erosion and deposition are also generally slower. Iron meteorites look very different to martian rocks (or for that matter stony meteorites on the surface) and so stand out.

« Last Edit: 01/18/2017 01:22 am by Dalhousie »

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"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

Possible Mud Cracks Preserved in Martian RockThe network of cracks in this Martian rock slab called "Old Soaker" may have formed from the drying of a mud layer more than 3 billion years ago. The view spans about 3 feet (90 centimeters) left-to-right and combines three images taken by the MAHLI camera on the arm of NASA's Curiosity Mars rover.Credits: NASA/JPL-Caltech/MSSSFull image and captionMars Rover's Mastcam View of Possible Mud CracksThis view of a Martian rock slab called "Old Soaker," which has a network of cracks that may have originated in drying mud, comes from the Mast Camera (Mastcam) on NASA's Curiosity Mars rover. It was taken on Dec. 20, 2016. The slab is about 4 feet long.Credits: NASA/JPL-Caltech/MSSSFull image and captionPossible Signs of Ancient Drying in Martian RockA grid of small polygons on the Martian rock surface near the right edge of this view may have originated as cracks in drying mud more than 3 billion years ago. Multiple Dec. 20, 2016, images from the Mastcam on NASA's Curiosity Mars rover were combined for this view of a rock called "Squid Cove."Credits: NASA/JPL-Caltech/MSSSFull image and captionScientists used NASA's Curiosity Mars rover in recent weeks to examine slabs of rock cross-hatched with shallow ridges that likely originated as cracks in drying mud.

"Mud cracks are the most likely scenario here," said Curiosity science team member Nathan Stein. He is a graduate student at Caltech in Pasadena, California, who led the investigation of a site called "Old Soaker," on lower Mount Sharp, Mars.

If this interpretation holds up, these would be the first mud cracks -- technically called desiccation cracks -- confirmed by the Curiosity mission. They would be evidence that the ancient era when these sediments were deposited included some drying after wetter conditions. Curiosity has found evidence of ancient lakes in older, lower-lying rock layers and also in younger mudstone that is above Old Soaker.

"Even from a distance, we could see a pattern of four- and five-sided polygons that don't look like fractures we've seen previously with Curiosity," Stein said. "It looks like what you'd see beside the road where muddy ground has dried and cracked."

The cracked layer formed more than 3 billion years ago and was subsequently buried by other layers of sediment, all becoming stratified rock. Later, wind erosion stripped away the layers above Old Soaker. Material that had filled the cracks resisted erosion better than the mudstone around it, so the pattern from the cracking now appears as raised ridges.

The team used Curiosity to examine the crack-filling material. Cracks that form at the surface, such as in drying mud, generally fill with windblown dust or sand. A different type of cracking with plentiful examples found by Curiosity occurs after sediments have hardened into rock. Pressure from accumulation of overlying sediments can cause underground fractures in the rock. These fractures generally have been filled by minerals delivered by groundwater circulating through the cracks, such as bright veins of calcium sulfate.

Both types of crack-filling material were found at Old Soaker. This may indicate multiple generations of fracturing: mud cracks first, with sediment accumulating in them, then a later episode of underground fracturing and vein forming.

"If these are indeed mud cracks, they fit well with the context of what we're seeing in the section of Mount Sharp Curiosity has been climbing for many months," said Curiosity Project Scientist Ashwin Vasavada of NASA's Jet Propulsion Laboratory in Pasadena. "The ancient lakes varied in depth and extent over time, and sometimes disappeared. We're seeing more evidence of dry intervals between what had been mostly a record of long-lived lakes."

Besides the cracks that are likely due to drying, other types of evidence observed in the area include sandstone layers interspersed with the mudstone layers, and the presence of a layering pattern called cross-bedding. This pattern can form where water was flowing more vigorously near the shore of a lake, or from windblown sediment during a dry episode.

Scientists are continuing to analyze data acquired at the possible mud cracks and also watching for similar-looking sites. They want to check for clues not evident at Old Soaker, such as the cross-sectional shape of the cracks.

The rover has departed that site, heading uphill toward a future rock-drilling location. Rover engineers at JPL are determining the best way to resume use of the rover's drill, which began experiencing intermittent problems last month with the mechanism that moves the drill up and down during drilling.

Curiosity landed near Mount Sharp in 2012. It reached the base of the mountain in 2014 after successfully finding evidence on the surrounding plains that ancient Martian lakes offered conditions that would have been favorable for microbes if Mars has ever hosted life. Rock layers forming the base of Mount Sharp accumulated as sediment within ancient lakes billions of years ago.

On Mount Sharp, Curiosity is investigating how and when the habitable ancient conditions known from the mission's earlier findings evolved into conditions drier and less favorable for life. For more information about Curiosity, visit:

This is rather curious considering how rare they are on Earth that it keeps coming across metallic meteorites on Mars.

Not really surprising. On Earth they rust quite quickly, on Mars they don't. Processes of erosion and deposition are also generally slower. Iron meteorites look very different to martian rocks (or for that matter stony meteorites on the surface) and so stand out.

Mars has less atmosphere and objects would hit the ground faster. Would stony meteorites disintegrate under these conditions?

This is rather curious considering how rare they are on Earth that it keeps coming across metallic meteorites on Mars.

Not really surprising. On Earth they rust quite quickly, on Mars they don't. Processes of erosion and deposition are also generally slower. Iron meteorites look very different to martian rocks (or for that matter stony meteorites on the surface) and so stand out.

Mars has less atmosphere and objects would hit the ground faster. Would stony meteorites disintegrate under these conditions?

John

They might fragment a bit more, being less tenacious than irons. But stony meteorites are just mafic to ultramafic rocks, unless they were very different from the substrate without a close examination.

While probably impact ejecta rather than a meteorite, Bounce rock encountered by Oppotunityearly in the mission is an example of a rock that stood out from the surrounds.

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"There is nobody who is a bigger fan of sending robots to Mars than me... But I believe firmly that the best, the most comprehensive, the most successful exploration will be done by humans" Steve Squyres

A positional update that is exciting to me. Curiosity is now only about 100m from beginning to cross the long stretch of dunes that have lain between the rover and Mt. Sharp ever since landing. In a couple of weeks Curiosity should finally be across and be ready to start climbing up to Hematite Ridge.